Objectives: The aim of the study was to characterize the PAH exposure level based on 1-hydroxypyrene (1-HP) in urine of Polish pregnant women and to assess the relationship between PAH and factors such as smoking, environmental tobacco smoke exposure, place of residence, heating and cooking method. Materials and Methods: The study population included in this analysis consisted of 449 pregnant women who had been the subjects of the prospective Polish Mother and Child Cohort study performed in 8 regions of Poland. The women were interviewed three times during pregnancy (once in each trimester). 1–HP concentration in urine was chosen as the biomarker of exposure to PAH. The urine sample was analysed using high performance liquid chromatography (HPLC). The active and passive smoking exposure was verified by saliva cotinine, analysed by high performance liquid chromatography coupled with tandem mass spectrometry (LC-MSMS) and isotope dilution method. Results: 1-HP concentration in urine ranged from 0.02 to 10.2 μg/g creatinine with the geometric mean (GM) 0.4 μg/g creatinine. The significantly higher concentration of urinary 1-HP in pregnant women was observed for summer collection (GM ratio: 1.1; p = 0.01), among smokers (GM ratio: 1.7; p < 0.001) and for the women living in big cities (GM ratio: 1.3; p = 0.001). Conclusions: The significantly higher concentration of urinary 1-HP in pregnant women was observed for summer collection, among smokers and those living in big cities.